Tihar Jail authorities today admitted before a court here that the prison was not completely free from use of mobile phones as jammers installed there did not cover each part. Eight mobile phones jammers have been installed in six jails primarily to cover high risk wards,special security wards and the prison where inmates having potential to use mobile phones are kept, a report submitted on behalf of Director General of prison said. It pointed out that the jammers have been installed in jail number one,two,three,four,seven,eight and nine which have been controlling cellular phone activities besides blocking the use of GSM/CDMA phones,sms and picture sending. The report filed in the court of Chief Metropolitan Magistrate Kaveri Baweja admitted the jammers had a limited range of blocking use of mobile phones and the entire area has not been covered. The courts order seeking a reply from the jail authorities came on a report submitted to it by Assistant Commissioner of Police,Special Cell,Sanjeev Kumar Yadav on October 13 stating that mobile phones were being operated from high-security Tihar jail despite jammers. The Delhi Polices Special Cell was asked to conduct an inquiry into the issue after an undertrial had on May 29 created a flutter in the court by producing a SIM card from his mouth and claiming inmates used mobile phones inside Tihar jail.